1. Technical Field
This invention relates generally to an adapter for mounting a pressure-sensing transmitter in a vertical orientation, and more particularly to such an adapter that is suitable for use in either gas or liquid pressure sensing applications.
2. Background Art
Multi-valve manifolds have been used to mount pressure sensing transmitters such as Rosemount.RTM. Coplanar.TM. style pressure transmitters. Such multi-valve manifolds are adapted for specific use in either a gas or in a liquid process application. Threaded plugs are typically installed in test ports on the top of the valve, and the valve is constructed in such a manner that prevents it from being reversed end for end, thus requiring separate configurations for liquid service and gas service applications. Additionally, it is difficult to drain condensate from the pressure cavities of the manifold and transmitter in order to avoid calibration errors. Also, since pressure sensing transmitters are now generally mounted directly to a multi-valve manifold in a field environment, it is difficult to accurately tighten the mounting bolts to assure that the high torque requirements specified by the transmitter manufacturer are met.
The present invention is directed to overcoming the problems set forth above. It is desirable to have a simple adapter that can be directly mounted to a standard horizontal mount blocking manifold, which thereby places the transmitter sensing foils in a vertical plane. As the result of the transmitter sensing foils being disposed in a vertical plane, condensate or deposits on the foils will not affect measurement accuracy, and the foil face can be either fully vented or fully immersed in the pressure media. This is impossible with horizontally positioned foils. It is also desirable to have an adapter that is reversible end for end (top for bottom) so that the pressure transmitter can be used in either liquid or gas service applications. It is also desirable to have a full drain and vent adapter for pressure sensing transmitters that has a foil cavity design in the adapter that allows full drain or vent even if the adapter is misaligned vertically by up to 15%. Furthermore, it is desirable to have such a full drain and vent adapter for mounting pressure-sensing transmitters that allows factory or shop torquing of the transmitter head to the manufacturer's specified high torque values, and additionally protects the sensing foils during shipping, handling, and installation of the pre-assembled unit at a field site.